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<title>Groovy Goodness: Using the Subscript Operator on Iterators</title>

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<h3 class="post-title">Groovy Goodness: Using the Subscript Operator on Iterators</h3>

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<p>Since Groovy 1.7.2 we can use the subscript operator for the <code>Iterator</code> class through the <code>getAt()</code> method. But we have to keep in mind the index value we use depends on a previous invocation of the subscript operator. Let's see this with an example:</p>
<pre class="brush:groovy">
def list = ['Groovy', 'Grails', 'Griffon', 'Gradle']
def iterator = list.iterator()

assert 'Groovy' == iterator[0]
assert 'Gradle' == iterator[-1]
assert !iterator[1]  // Iterator is exhausted.

iterator = list.iterator()  // Get new iterator.
def newList = []
(0..&lt;list.size()).each {
 newList &lt;&lt; iterator[0]  // Index 0 is next element.
}
assert 'Groovy,Grails,Griffon,Gradle' == newList.join(',')
</pre
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